JP2653968B2 - Electric circuit board and its manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric circuit board and an electric circuit board.
And , in particular, to a process effective for metallization on an electric circuit board such as a printed wiring board, and a novel electric circuit board produced by the process.
Specifically, the present invention does not require an operation of manufacturing a metal circuit by etching a substrate to which a metal has been previously attached, and directly produces a metal circuit pattern by electroplating on a necessary portion without using a catalyst. A method for patterning a conductive polymer using a catalyst that reduces or disappears is applied.

[0002]

2. Description of the Related Art A conventional electric circuit such as a printed wiring board is formed by applying a photoresist material such as a photosensitive resin to an insulating substrate covered with a conductive material such as copper, gold, and tin oxide. After applying a mask and irradiating ultraviolet rays etc., the photoresist agent is cured, and after removing the uncured part, by chemical etching etc.
Unnecessary copper foil portions are removed to form an electric circuit, and the process is very complicated. In addition, there is a disadvantage that there is a step of wasting resources and energy, such as removing the resist and dissolving and removing most of the metal.

[0003] A full-additive method, which is one of the methods for manufacturing a through-hole plated printed wiring board that improves this point, is to produce a metal circuit such as copper by electroless plating without using a substrate on which a metal foil is adhered. In this method, the etching step can be omitted, but there is a problem in the management of the electroless plating solution, the working environment, and the like , and the method does not occupy the main method of manufacturing a printed circuit board.

On the other hand, as a conductor that replaces the conventional metal,
Conducting polymers have attracted attention, and various conductive polymers have been synthesized and studied. However, their insolubility and infusibility have a problem in workability, and their applications have been limited.

In order to improve this point, some of the present inventors have provided a method for producing a conductive polymer pattern (Japanese Patent Application No. 4-69647). In this method, a pattern of a conductive polymer is produced by utilizing the property of a catalyst in which the polymerization ability of a monomer of the conductive polymer changes by irradiation with light, and specifically, iron (III) chloride or the like is used. A material that becomes a catalyst for oxidative polymerization of pyrrole and is reduced by light and loses its oxidizing property is applied as a solution to the surface of another material, or a composition mixed with a polymer or the like is formed into a thin film, film, or plate. By irradiating ultraviolet light or visible light with a mask pattern adhered to the mask pattern, the oxidizing property of the light-irradiated portion is eliminated and pyrrole is not polymerized.

In other words, a conductive pattern can be produced by generating polypyrrole, which is a conductive polymer, only in the non-irradiated portion. However, in this method, the conductivity of the conductive polymer pattern is lower than that of a metal such as copper. Therefore, this method can be applied to a low-current electronic circuit such as a light emitting diode or a liquid crystal. There were insufficient points, such as the inability to substitute the circuit as it was.

[0007]

SUMMARY OF THE INVENTION The main object of the present invention is to:
An object of the present invention is to provide a manufacturing process of a metal electric circuit board whose process is simple using a pattern of a conductive polymer produced using a photoreactive oxidation catalyst, and to provide a novel electric circuit board which is characteristic.

Another object of the present invention is to provide a manufacturing process that does not use a metal foil-clad laminate as a substrate and does not require an etching step or a resist removing step.

It is a further object of the present invention to provide a process for simultaneously producing plated through holes.

Another object of the present invention is to provide a manufacturing process for shortening the steps of a conventional printed wiring board and the like and saving resources and energy.

[0011]

An electric circuit board according to the present invention.
Is formed on the substrate and the catalytic activity is reduced or lost by light
The mask pattern of the electric circuit is applied to the layer containing the catalyst
And irradiates the catalyst with the catalyst through the electric circuit.
Catalyst layer degraded or eliminated in the catalyst part other than the channel
And the catalyst part whose catalytic activity has been reduced or eliminated by light
The catalyst layer has not been removed,
After polymerization, a monomer that forms a conductive polymer after polymerization
The mask pattern of the electric circuit obtained by contact
Conductive polymer circuit pattern formed in corresponding shape
A metal to the conductive polymer circuit pattern
By plating, the conductive polymer circuit pattern
Metal circuit pattern formed in the shape of
It is characterized by. The metal circuit pattern has a high conductivity.
Contacting the molecular circuit pattern with the conductive polymer circuit pattern;
With at least a part of the conductor that is supplying current by touch
In an electroplating solution and electroplating
It may be one that has been formed. The conductive polymer cycle
Conductors that supply current by contacting the circuit pattern
For example, a metal paste is used. Specifically, a silver paste is used.
I can do it. The catalyst layer has, for example, a catalytic activity by the light.
Mixing the catalyst and the Matrigel Kkusuporima to reduce or eliminate
It is formed from a combination. In addition, the catalyst
The layer is catalyzed by the light without the matrix polymer
May be formed from a catalyst whose activity decreases or disappears
No. Incidentally, after forming the conductive polymer circuit pattern, the
Prior to electroplating, the light reduces the catalytic activity or
The lost catalyst portion may be removed. Mentioned above
The manufacturing method of the electric circuit board is performed, for example, as follows.
You. That is, an electric circuit including the following steps a) to d)
A method for manufacturing a substrate may be used. a) A catalyst whose catalytic activity decreases or disappears due to light on a substrate
B) forming a mask pattern of an electric circuit on the catalyst layer.
And irradiates the catalyst with the catalyst through the electric circuit.
Reducing or eliminating the catalyst portion other than the road; c) a catalyst whose catalytic activity has been reduced or eliminated by the light
Without removing the part, the catalyst layer
Monomer that forms a conductive polymer after polymerization
To correspond to the mask pattern of the electric circuit.
Forming a conductive polymer circuit pattern in a bent shape; d) applying a metal to the conductive polymer circuit pattern.
The conductive polymer circuit pattern is
Forming a metal circuit pattern in the shape of the metal pattern. This
As described above, the shape of the electric circuit is previously determined by the steps a) to c).
Polymerized into a polymer, and directly into the conductive polymer circuit pattern.
If the pattern itself is formed, the metal
It can be easily done by the step d).
A large amount of metal is not discarded by etching. Ma
In addition, the conductive polymer itself is a troublesome process to remove extra parts.
It is not necessary. In the step a), the catalytic activity is increased by the light.
Mix the degraded or disappearing catalyst with the matrix polymer.
From the combination, the catalyst layer may be formed.
Or with the light without using a matrix polymer
The catalyst layer is removed from the catalyst whose catalytic activity decreases or disappears.
It may be formed. The step c) and d)
Between the steps, the catalyst activity is also reduced by the light extinction
By performing the process of removing the lost catalyst part
Is also good. Note that the step d) is performed by the conductive polymer circuit.
Circuit pattern and the conductive polymer circuit pattern
At least a part of the conductor supplying the electric current is
By plating in a plating solution, the metal
A circuit pattern may be formed. The conductivity
Conductivity supplying current in contact with polymer circuit pattern
The body is, for example, a metal paste, and more specifically, a silver paste.
Rust. Also , through plating in electroplating
Plating for holes and the like can be performed simultaneously.

In the present invention , the catalytic activity is reduced by light or
The disappearing catalyst (hereinafter referred to as "catalytic activity reduction type catalyst") is contained in the substrate itself in advance, and is used alone or as a solution in the presence of another substance to form a coating film applied on the material surface, or a matrix polymer and other substances are used. The mixed solution is used as a composite film or film obtained by a film forming method such as a casting method or a bar coating method. The layer containing the catalyst is irradiated with light such as ultraviolet light through a mask, a negative, a positive, or the like, and after printing the image, the monomer vapor of the conductive polymer is removed without removing the catalyst that has reduced or lost the catalytic activity. Is contacted or immersed in a solution containing a monomer, the monomer does not polymerize in a portion where light is irradiated, and a monomer polymerizes only in a portion where light is blocked, thereby forming a conductive pattern. Only on this conductive polymer pattern,
In the case of forming an electrode , for example, the terminal of the conductive polymer pattern is covered with a conductor such as silver paste, and the silver paste portion is connected to the electrode. This is put in the electrolytic plating solution so that a part of the silver paste part is also in the solution, and when the metal is plated, the metal is gradually deposited from the conductive polymer pattern portion close to the electrode and gradually grows as a whole, A metal circuit is formed on the conductive polymer pattern.

According to the circuit formation according to the present invention, the catalyst is applied to the surface of another material by coating or other general thin film forming method.
Because it is easy to apply the layer containing the active light reducing catalyst , it can be applied to any solid material surface such as polymer, ceramic, metal, paper, and cloth.

[0014] catalytically active optical reduction type that uses in the present invention
As the catalyst , metal compounds such as iron and copper are effective,
Particularly preferred compounds include iron (III) compounds such as iron (III) chloride and iron (III) sulfate, and copper chloride (I).
I) and copper (II) compounds such as copper (II) bromide. These metal compounds may be used as a mixture.
As the matrix polymer for incorporating the catalyst with reduced catalytic activity light, any polymer that is miscible with the catalyst with reduced catalytic activity can be used .
Are preferred, such as polyvinyl alcohol, polyvinyl butyral, polyvinyl acetate, polymethyl methacrylate, polyacrylonitrile, and epoxy resin.
New Natural polymers such as gelatin and cellulose can also be used.

The monomers used in the present invention include the following:
Is a monomer that generates a conductive polymer, for example,
There are pyrroles and thiophenes. Examples of pyrroles include , for example, unsubstituted pyrrole, N-substituted pyrrole and ring-substituted pyrrole. Pyrrole as described above
By copolymerizing 5-membered cyclic compound together such kind or thiophenes
Or, or, such as the above-mentioned pyrroles and thiophenes
It is also possible to copolymerize a 5-membered ring compound with another copolymerizable monomer. The polymerization of these monomers, the conductivity of the conductive polymer, if more than about 0.01 S / cm, the
Since it is possible to perform electroplating on the upper surface, it is not necessary to particularly increase the conductivity, and a method of vapor phase polymerization at room temperature in the air or immersion polymerization in a solution is sufficient, and the equipment and the like can be simplified.

In the present invention, the above-mentioned catalytically active light-reducing type
Use medium alone without using matrix polymer
In this case, the solution is applied as a solution of an organic or inorganic solvent such as water, alcohols such as methanol, ketones such as acetone, halogenated hydrocarbons such as chloroform and 1,2-dichloroethane, and hydrocarbons such as benzene . Of course, from a solution of various solvents that can dissolve the matrix polymer together with the matrix polymer , a catalyst, as a composite film by a method such as a bar coating method ,
Layers can also be formed. The composite with the matrix polymer may be formed by another general method for producing a membrane , for example, a method of forming a catalyst layer in a shape of a film or plate produced by kneading and extrusion with the matrix polymer.

For the irradiation of the catalyst layer with light , any device that generates the sun, visible light, ultraviolet light, or light containing these can be used. For example , metal electroplating
In can all copper, nickel, Metoshi Haji chromium, metals capable electroplating in an acidic bath applications.

[0018]

When the process of forming the electric circuit board according to the present invention is performed , the conductive polymer circuit pattern is formed in the shape of the electric circuit.
The polymerization of the conductive polymer that forms the catalyst is carried out by touching the catalyst layer in the gas phase or in a solution, in particular, the part where light is masked.
The catalytically active light-reducing catalyst maintains sufficient catalytic activity.
Therefore, the portion corresponding to the mask pattern is markedly polymerized.
Activation, which allows the mask pattern
A circuit pattern made of a conductive polymer is formed. this
As before, a circuit pattern of conductive polymer is formed
That the circuit pattern is conductive,
By immersing in the metal ion solution, the circuit pattern
Can be electroplated into a shape, directly by metal
A circuit pattern of the circuit is formed. Therefore, extra
Since the metal layer is not formed, remove the metal layer as before.
And no chemical treatment is required. In addition, the use of a catalyst layer
The part inactivated by the irradiation of
The conductive polymer circuit pattern is shaped according to the mask pattern
As such, there is no need for a catalyst removal step. However, touch
Such as when using only the catalyst with reduced active light.
What is easy to peel off should be removed with a solvent before plating etc.
No. Removal with this solvent is different from conventional metal layer removal.
It is extremely simple and can be manufactured at low cost.
Does not lead to an increase in Using matrix polymer
If a sufficiently adherent catalyst layer is formed,
Does not need to be removed at all, thus reducing production costs.
Do not invite layers. In this method, the same applies to through holes.
Precious metal seed process before electrolytic plating
It is also possible to eliminate the electroless plating step.

The conductivity of the conductive polymer is 0.01
Since electroplating can be performed if the S / cm is about S / cm or more, it is not necessary to increase the conductivity, and what is polymerized at room temperature in the atmosphere is sufficient, and the equipment can be simplified. In addition, although the Example was shown below, it is not specifically limited to these.

[0020]

[ Example 1] 3 parts of an epoxy resin composition, 10 parts of a diluent in advance and iron (III) chloride hexahydrate as iron (III) chloride in a weight ratio of 3: 7 with the epoxy resin composition. And dissolved in a completely dissolved solution. After applying this solution to the polyester film surface by a bar coating method,
For 20 minutes to produce a thin film having a thickness of about 10 μm.
A mask pattern on which an electric circuit was constructed was superimposed on the obtained thin film, and light was irradiated from a distance of 1 m with a 2 kW halogen lamp for 30 minutes. After irradiation with light, the pyrrole monomer was placed in a closed container containing the pyrrole monomer at the bottom, and was subjected to gas phase polymerization at 20 ° C. for 1 hour. As a result, black polypyrrole was formed only at the mask portion. Next, after vacuum drying at room temperature for 1 hour, the resultant was immersed in methanol to extract and remove soluble iron compounds, and then air-dried. The conductivity measured by the four-terminal method was 0.2 S / cm due to the generated polypyrrole in the mask portion, while the light-irradiated portion was insulative. One end of the polypyrrole pattern forming portion is coated with a silver paste, connected to a negative electrode, so that a part of the silver paste portion is also in a solution in a copper sulfate-sulfuric acid mixture, and 50 mA of copper is used for a positive electrode. When electroplating by applying current,
Copper was deposited on the polypyrrole pattern from a portion close to the electrode, and gradually grew over the entire surface to form a copper pattern based on the polypyrrole pattern.

Example 2 2 parts of polyvinyl acetate was dissolved in 20 parts of ethyl acetate, and anhydrous iron (III) chloride was added to this solution at a weight ratio of 30 to the solid content.
% And completely dissolved. This solution was applied to the surface of a polyester film by a bar coating method.
After drying at 0 ° C. for 20 minutes, a thin film having a thickness of about 10 μm was prepared. Thereafter, light irradiation was performed in the same manner as in Example 1, and 20
When pyrrole was subjected to gas phase polymerization at 1 ° C. for 1 hour, polypyrrole was formed only in the mask pattern portion where light was blocked, and a pattern having a conductivity of 0.4 S / cm was obtained. This was electroplated in the same manner as in Example 1 to obtain a copper pattern.

Example 3 Iron (III) hexahydrate was added to 100 parts of an acrylic emulsion as iron (III) chloride in a weight ratio of 30% to prepare a completely dissolved solution. Thereafter, the same operation as in Example 2 was performed, and after pyrrole was subjected to gas phase polymerization at -30 ° C. for 57 hours, it was immersed in methanol to extract and remove residual iron salts, and air-dried. The conductivity was 3.2 S / cm in the mask portion while the light irradiation portion was insulative. This was electroplated in the same manner as in Example 1 to obtain a copper pattern.

Example 4 2 parts of polymethyl methacrylate were dissolved in 20 parts of ethyl acetate (or methyl ethyl ketone), and anhydrous iron (III) chloride was added to this solution so as to be 30% by weight of the solid content. Completely dissolved. Thereafter, a composite film was prepared in the same manner as in Example 2, and after irradiating with light for 15 minutes through a mask pattern and immersing in a 5% n-hexane solution of pyrrole for 15 seconds at room temperature, polypyrrole was applied only to the mask pattern portion where light was blocked. A pattern having a conductivity of 0.07 S / cm was obtained. Thereafter, electroplating was performed in the same manner as in Example 1 to obtain a copper pattern.

Example 5 Copper (I) chloride was added to a 10% aqueous solution of polyvinyl alcohol such that copper (II) chloride in the solid content was 30% by weight.
I) Dihydrate was added and completely dissolved. Thereafter, the same operation as in Example 2 was carried out, and a polypyrrole pattern was formed in a pyrrole gas phase polymerization condition at 20 ° C. for 30 minutes. The conductivity of the polypyrrole pattern after heating at 150 ° C. for 10 minutes to insolubilize the polyvinyl alcohol was 2.86 S / cm. When this pattern was electroplated under the same conditions as in Example 1, a copper pattern based on the mask pattern was obtained.

Example 6 A 10% methanol solution of iron (III) chloride was applied to the surface of an acetate film, air-dried at room temperature in a dark place, and irradiated with light under the same conditions as in Example 1 to remove pyrrole by 20%. ° C, 90
Vapor phase polymerization was performed for minutes. The mask portion formed by the mask pattern showed a conductivity of 0.53 S / cm. Next, Example 1
Copper plating could be formed directly on the surface of the acetate film by performing copper plating under the same conditions as described above.

Example 7 When the gas phase polymerization of pyrrole in Example 3 was carried out at 20 ° C. for 1 hour, a polypyrrole pattern having a conductivity of 1.69 S / cm was formed. One end of this polypyrrole pattern was covered with a silver paste and connected to a negative electrode, and a current of 50 mA was passed through a nickel plate to a positive electrode in a nickel sulfate-nickel chloride-boric acid mixed solution to perform electroplating. Nickel was deposited, and a nickel electric circuit pattern was obtained.

[0027]

According to the electric circuit board of the present invention and its manufacturing method, a metal electric circuit such as copper can be formed on the board by a simple method.
In addition, since the metal wiring can be formed only on a necessary portion by electroplating, a substrate material to which a copper foil or the like is bonded as in the past is not required.

Further, as compared with the flow chart of the printed circuit board manufacturing process according to the present invention of FIG. 1 and the flow chart of the conventional printed circuit board manufacturing process of FIG. 2, an etching step for removing and discarding most of the copper foil. And the step of removing the resist can be omitted, which not only saves a great deal of resources, but also allows the plating of the through-holes at the same time.
Since an expensive palladium catalyst or an electroless copper bath is not required, problems such as wastewater treatment and treatment of harmful substances can be greatly reduced. That is, unlike a complicated manufacturing method of a printed wiring board or the like, a process can be shortened, equipment can be rationalized, resources can be saved, energy can be saved, and pollution can be reduced.

Further , the catalytic activity decreases or disappears due to light.
Circuit pattern made of conductive polymer using catalyst
During the formation of the catalyst layer, the light-irradiated part of the catalyst layer is removed.
Efficient conductive polymer circuit pattern
Is formed. In addition, the conductive polymer circuit pattern
After completion, place the conductive polymer circuit pattern
If it is necessary to remove some of the catalyst layer, it can be easily removed with a solvent.
Production efficiency is high and a large amount of energy is
do not need. Using a matrix polymer,
If a strong catalyst layer is formed, there is no need to remove it,
Very high production efficiency. Also , use a conductive polymer in advance.
Since a circuit pattern is formed, not only epoxy laminates but also various polymers, ceramics, metals,
Paper, cloth, and the like can be used, and a metal circuit can be easily formed on the surface thereof. For this reason, there is a feature that the application range as an electronic material is remarkably wide.

[Brief description of the drawings]

FIG. 1 is a flowchart of a printed circuit board manufacturing process according to the present invention.

FIG. 2 is a flowchart of a conventional printed circuit board manufacturing process.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Yukihiro Natsume 24 Fukami, Kamikazu, Oji, Jimaji-cho, Kaifu-gun, Aichi Prefecture (72) Inventor: Kazuyoshi Saji Jika-Jitsu, Jojime-cho, Kaifu-gun, Aichi 24 Fukami Inside Aika Kogyo Co., Ltd. (56) References JP-A-64-51691 (JP, A) JP-A-2-273926 (JP, A)

Claims (12)

(57) [Claims] 1. A catalyst which is formed on a substrate and whose catalytic activity is reduced by light.
Is the mask pattern of the electric circuit against the layer containing the disappearing catalyst.
Irradiate light through the turn to increase the catalytic activity of the catalyst.
The catalyst part other than the electric circuit
Of the catalyst layer and the catalyst part whose catalytic activity has been reduced or eliminated by light.
The catalyst layer not polymerized is polymerized by the catalyst.
After polymerization, contact monomer that generates conductive polymer
Corresponding to the mask pattern of the electric circuit obtained
A conductive polymer circuit pattern formed in a uniform shape, and electrically conductive metal on the conductive polymer circuit pattern.
The shape of the conductive polymer circuit pattern.
An electric circuit board comprising: a metal circuit pattern formed in a shape . 2. The method according to claim 1, wherein the metal circuit pattern includes the conductive part.
Contact with the child circuit pattern and the conductive polymer circuit pattern
And at least a part of the conductor supplying the current,
Formed by electroplating in an electroplating solution
The electric circuit board according to claim 1, wherein
Board. 3. Contacting the conductive polymer circuit pattern
The conductor supplying the current must be a metal paste
The electric circuit board according to claim 2, wherein: 4. The catalyst layer according to claim 1 , wherein the catalytic activity is reduced by the light.
Mixed with the disappearing catalyst and matrix polymer
4. The method according to claim 1, wherein the first member is formed from a material.
The electric circuit board according to any one of the above. 5. The catalyst layer according to claim 1 , wherein the catalytic activity is reduced by the light.
Characterized by being formed from a catalyst that disappears
The electric circuit board according to claim 1. 6. After forming the conductive polymer circuit pattern,
Before the electroplating, the light reduces the catalytic activity.
Or by removing the lost catalyst part.
The electric circuit board according to claim 5. 7. A method for producing an electric circuit board comprising the following steps a) to d) . a ) A catalyst whose catalytic activity decreases or disappears due to light on a substrate
B) forming a mask pattern of an electric circuit on the catalyst layer.
And irradiates the catalyst with the catalyst through the electric circuit.
Reducing or eliminating the catalyst portion other than the road; c) a catalyst whose catalytic activity has been reduced or eliminated by the light
Without removing the part, the catalyst layer
Monomer that forms a conductive polymer after polymerization
To correspond to the mask pattern of the electric circuit.
Forming a conductive polymer circuit pattern in a bent shape; d) applying a metal to the conductive polymer circuit pattern.
The conductive polymer circuit pattern is
Forming a metal circuit pattern in the shape of the metal pattern. 8. In the step (a), the catalytic activity is low by the light.
Mixing down or disappearing catalyst with matrix polymer
Forming the catalyst layer from
A method for manufacturing an electric circuit board according to claim 7. 9. In the step (a), the catalytic activity is low by the light.
Forming the catalyst layer from a catalyst that falls or disappears
The method for producing an electric circuit board according to claim 7, wherein: 10. The method according to claim 10, wherein the step c) and the step d) are performed between
Catalyst part whose catalytic activity has been reduced or eliminated by the light
10. The method according to claim 9, wherein a step of removing is performed.
Manufacturing method of electric circuit board. 11. The method according to claim 1 , wherein the step (d) is performed by using the conductive polymer circuit.
Circuit pattern and the conductive polymer circuit pattern
At least a part of the conductor supplying the electric current is
By plating in a plating solution, the metal
A circuit pattern is formed.
0. The method for producing an electric circuit board according to any one of the above items. 12. A conductive polymer circuit pattern,
The conductor that supplies the current is metal paste.
The method for manufacturing an electric circuit board according to claim 11, wherein